load 38 - Thats very cool for a prescot... are you sure?... Thats lower than an AMD (supposed to be cooler) with no load on standard heatsink/fan...
Because the older card did it, it can't be the new card.
Also, because the demo did it, it can't be the game either... so it must be something to do with hardware in that case.
CPU TEMP PROTECTION:
The CPU temperature does worry me though, and it could be this.
This would cause the game to slowdown and crash if the CPU was getting too hot playing this game, but Pentium have a great protection feature which will slow the core clock (frequency) down until temperatures reach a safe level to stop the CPU burning up which would stop any game in its tracks, even with a good card...
When you say that temperature is on load, is it taken when the game is going barmy?
I say this because the core frequency could have already dropped probably when you check, giving a safe temperature of 28 degrees
(since this is too low for a pentium 4 prescot in load and is why I think its because the frequency inside dropped, which would also be why you only get around 16fps in the game, and it dies))
So I'd check the cpu heatsink and fan is working all the time by taking off the side and watching it while playing, and if it stutters or stops when this starts happening, or even slows down, replace it immediatly
If it doesn't do anything weird, I would then turn the PC off, take the heatsink off, and re-apply thermal paste (buy soem from any computer store) (plus don't apply too much, only a few layers thick as too much would cause it damage too) and then put it back and try again.
I hope this fixes it for you and you understand more